In order to effectively use a sewing machine, it is very desirable to control the feeding of the fabric through the machine to achieve special effects on the material being sewn. To that end, many devices are known to assist this function. These devices primarily employ mechanisms mechanically arranged to achieve an elliptical motion of the fabric feeder.
This elliptical motion results from a vertical motion imparted to the cloth feeder combined with a horizontal motion. The feeder rises up to engage the fabric and simultaneously starts moving the fabric horizontally. The vertical motion reaches its peak and begins to drop down as the horizontal motion continues to feed the fabric. When the feeder drops below the cloth support plate the fabric stops moving, the feeder continues down and starts returning horizontally. The fabric is held stationary during this return cycle by the clamping pressure of the presser foot. The feed returns to the start position and begins the vertical motion all over again, repeating the cycle.
The current mechanical feed mechanism incrementally moves the fabric in a straight line. The sewing machine operator must guide the fabric manually to achieve a curved stitch pattern. There are available various add on devices to manipulate the fabric as comes into the sewing machine or during the sewing process itself to assist or replace the sewing machine process itself. Also, in some sewn products, there could be a series of discreet areas to be sewn, not connected to each other. The operator must sew one area, stop, trim threads, reposition manually and start sewing the second area.
The current cloth feeding mechanisms are mechanically linked to the other sewing mechanisms (for example needle mechanism, hook mechanism, looper mechanisms, and so forth) to provide synchronous motions to produce a stitch. The prior art feed mechanism control features are also all mechanically arranged. Stitch length (the increment the fabric moves for each machine cycle) is adjusted by turning a dial to move a linkage, or by adjusting a mechanical eccentric, or by changing eccentric cams. These changes complicate the sewing process.
Better control of the fabric or material feeding through a sewing machine can greatly improve production and quality of sewn products. For the purposes herein fabric and material may be used interchangeably unless otherwise specified. To achieve this feeding of material or fabric with programmability and ease of control offers great advantages. Such features are currently unavailable in the art, unless the sewing machine has many complicated devices attached thereto.